Such closure devices serve to close a container which has an opening edge comprising an inner and an outer wall. The container can, for example, comprise a can, in particular, a drinks can, bottle, storage container or similar. Furthermore, the container itself can comprise plastic, metal, porcelain, glass or various other materials. The closure device has a sealing element whereby the opening of the container can be closed in a sealing manner. Known containers are usually closed in a sealing manner by closure devices, by pressing the seal in the closure device between the closure device itself and the container, in particular an opening edge. By this means, a seal is effected particularly in containers which build up an internal pressure. In this context, it is known that the contact pressure on the sealing element must be greater than the internal pressure forming or present in the container so that the closure device correspondingly seals the container. Such closure devices are, for example in drinks bottles, integrated in the lid which serves as a closure device and pressed by means of the thread with the drinks bottle so that the sealing effect of the closure device is produced by a corresponding deformation of the seal. It is also known to close a test tube with a rubber stopper, the rubber stopper being configured in a frustro-conical manner and being pressed with a high contact pressure into the opening edge of the test tube in order to close this. In this case, a deformation of the rubber stopper must also be effected by a corresponding contact pressure. Furthermore, for example, crown cork closures for bottles are known which also press the sealing element between the crown cork closure, which serves as a closure device, and the bottle edge. Such crown cork closures have the disadvantage that they are not re-usable. Furthermore, they can only be attached with the aid of mechanical devices in order to close the bottle. In addition, further numerous variants of closure devices for containers are known from the general prior art, which all exert a corresponding contact pressure from above or inside onto the sealing element in order to deform this or press on the opening edge.
Known, for example, from the document DE 103 12 237 A1 is a closure for a can in which the can closure is attached mechanically in an opening of the can lid. The closure itself has a multipart structure and has a hinged lid which is integrated on the closure device. The entire can can then be sealed with the aid of the closure lid. This closure device has the disadvantage that on the one hand, it must be previously connected to the can by production technology and on the other hand, it does not close the can in a gas-tight or pressure-tight manner.
Further known from the prior art is the document WO 2004/056667 A1 which is directed towards a closure device for a drinks can. This closure device is firmly riveted on the upper side of the drinks can and can, for example, close the opening of the drinks can or, if the closure device is turned away, release it. For this purpose the closure device is turned about the rivet on the casing upper side. This closure device also has the disadvantage that the closure device does not seal the opening in a pressure-tight manner. In this case, there is always the risk that the internal pressure can escape through the closure device. If the drinks can is located in a tilted state, the contents flow out. Furthermore, this closure device is difficult to handle since the closure device is disposed inside the flanged can edge. In addition, the can must be held firmly with one hand and the closure device operated with the other hand.